Rational design of a SOCS1-edited tumor-infiltrating lymphocyte therapy using CRISPR/Cas9 screens.

Cell therapies such as tumor-infiltrating lymphocyte (TIL) therapy have shown promise in the treatment of patients with refractory solid tumors, with improvement in response rates and durability of responses nevertheless sought. To identify targets capable of enhancing the antitumor activity of T cell therapies, large-scale in vitro and in vivo clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 screens were performed, with the SOCS1 gene identified as a top T cell-enhancing target. In murine CD8+ T cell-therapy models, SOCS1 served as a critical checkpoint in restraining the accumulation of central memory T cells in lymphoid organs as well as intermediate (Texint) and effector (Texeff) exhausted T cell subsets derived from progenitor exhausted T cells (Texprog) in tumors. A comprehensive CRISPR tiling screen of the SOCS1-coding region identified sgRNAs targeting the SH2 domain of SOCS1 as the most potent, with an sgRNA with minimal off-target cut sites used to manufacture KSQ-001, an engineered TIL therapy with SOCS1 inactivated by CRISPR/Cas9. KSQ-001 possessed increased responsiveness to cytokine signals and enhanced in vivo antitumor function in mouse models. These data demonstrate the use of CRISPR/Cas9 screens in the rational design of T cell therapies.

Pharmacokinetics, safety, and tolerability of BMS-986263, a lipid nanoparticle containing HSP47 siRNA, in participants with hepatic impairment.

BMS-986263 is a retinoid-conjugated lipid nanoparticle delivering small interfering RNA designed to inhibit synthesis of HSP47 protein, a collagen-specific chaperone protein involved in fibrosis development. This is a phase I, open-label, two-part study evaluating pharmacokinetics and safety of BMS-986263 in participants with hepatic impairment (HI). Part 1 (n = 24) of this study enrolled two cohorts with mild and moderate HI and a separate cohort of age- and body mass index (BMI)-matched participants with normal hepatic function. Part 2 enrolled eight participants with severe HI and eight age- and BMI-matched participants with normal hepatic function. All participants received a single intravenous 90 mg BMS-986263 infusion. Compared with normal-matched participants, geometric mean area under the plasma concentration-time curve time zero to the time of the last quantifiable concentration (AUC(0-T) ) and AUC from zero to infinity (AUC(INF) ) of HSP47 siRNA were similar in participants with mild HI and 34% and 163% greater in those with moderate and severe HI, respectively, whereas the maximum plasma concentration was ~25% lower in mild and moderate HI groups but 58% higher in the severe HI group than in the normal group. Adverse events were reported by two of eight, four of eight, and three of eight participants with mild, moderate, or severe HI, respectively; none were reported in the normal-matched group. Overall, single-dose BMS-986263 was generally safe and well-tolerated and dose adjustment is not considered necessary for participants with mild or moderate HI. Although available data do not indicate that dose adjustment should be performed in patients with severe HI; the optimal posology of BMS-986263 in patients with severe HI may be determined later in its clinical development when additional data to establish exposure-safety/efficacy relationship becomes available.

TLR3 Signaling Promotes the Induction of Unique Human BDCA-3 Dendritic Cell Populations.

Conventional and plasmacytoid dendritic cells (cDCs and pDCs) are the two populations of DCs that can be readily identified in human blood. Conventional DCs have been subdivided into CD1c(+), or blood dendritic cells antigen (BDCA) 1 and CD141(+), or BDCA-3, DCs, each having both unique gene expression profiles and functions. BDCA-3 DCs express high levels of toll-like receptor 3 and upon stimulation with Poly I:C secrete IFN-ß, CXCL10, and IL-12p70. In this article, we show that activation of human BDCA-3 DCs with Poly I:C induces the expression of activation markers (CD40, CD80, and CD86) and immunoglobulin-like transcript (ILT) 3 and 4. This Poly I:C stimulation results in four populations identifiable by flow cytometry based on their expression of ILT3 and ILT4. We focused our efforts on profiling the ILT4(-) and ILT4(+) DCs. These ILT-expressing BDCA-3 populations exhibit similar levels of activation as measured by CD40, CD80, and CD86; however, they exhibit differential cytokine secretion profiles, unique gene signatures, and vary in their ability to prime allogenic naïve T cells. Taken together, these data illustrate that within a pool of BDCA-3 DCs, there are cells poised to respond differently to a given input stimulus with unique output of immune functions.

Human XCR1+ dendritic cells derived in vitro from CD34+ progenitors closely resemble blood dendritic cells, including their adjuvant responsiveness, contrary to monocyte-derived dendritic cells.

Human monocyte-derived dendritic cell (MoDC) have been used in the clinic with moderately encouraging results. Mouse XCR1(+) DC excel at cross-presentation, can be targeted in vivo to induce protective immunity, and share characteristics with XCR1(+) human DC. Assessment of the immunoactivation potential of XCR1(+) human DC is hindered by their paucity in vivo and by their lack of a well-defined in vitro counterpart. We report in this study a protocol generating both XCR1(+) and XCR1(-) human DC in CD34(+) progenitor cultures (CD34-DC). Gene expression profiling, phenotypic characterization, and functional studies demonstrated that XCR1(-) CD34-DC are similar to canonical MoDC, whereas XCR1(+) CD34-DC resemble XCR1(+) blood DC (bDC). XCR1(+) DC were strongly activated by polyinosinic-polycytidylic acid but not LPS, and conversely for MoDC. XCR1(+) DC and MoDC expressed strikingly different patterns of molecules involved in inflammation and in cross-talk with NK or T cells. XCR1(+) CD34-DC but not MoDC efficiently cross-presented a cell-associated Ag upon stimulation by polyinosinic-polycytidylic acid or R848, likewise to what was reported for XCR1(+) bDC. Hence, it is feasible to generate high numbers of bona fide XCR1(+) human DC in vitro as a model to decipher the functions of XCR1(+) bDC and as a potential source of XCR1(+) DC for clinical use.

Teriflunomide attenuates immunopathological changes in the dark agouti rat model of experimental autoimmune encephalomyelitis.

Teriflunomide is an oral disease-modifying therapy recently approved in several locations for relapsing-remitting multiple sclerosis. To gain insight into the effects of teriflunomide, immunocyte population changes were measured during progression of experimental autoimmune encephalomyelitis in Dark Agouti rats. Treatment with teriflunomide attenuated levels of spinal cord-infiltrating T cells, natural killer cells, macrophages, and neutrophils. Teriflunomide also mitigated the disease-induced changes in immune cell populations in the blood and spleen suggesting an inhibitory effect on pathogenic immune responses.

Heart transplantation in diabetic recipients: a decade review of 161 patients at Columbia Presbyterian.

OBJECTIVE: Diabetes is considered by some transplant centers to be a relative contraindication for cardiac transplantation because of concerns regarding decreased survival, as well as increased incidence of infection and transplant coronary artery disease. We evaluated our experience with diabetic recipients over the last 10 years. METHODS: From January 1992 through June 2002, 881 patients underwent cardiac transplantation at New York Presbyterian Hospital. Of these, 161 (18.3%) were diabetic patients. Diabetic recipients were compared with a control group of 161 nondiabetic recipients matched for age, sex, cause of heart failure, United Network for Organ Sharing status, and immunosuppression era. Outcome measures included posttransplantation survival, incidence of infection, rejection, and transplant coronary artery disease. RESULTS: There was no statistically significant difference in survival between diabetic and nondiabetic recipients, with actuarial survival at 1, 5, and 10 years of 89.3%, 66.9%, and 45.6%, respectively, for diabetic patients and 87.4%, 78.8%, and 59.1%, respectively, for nondiabetic patients (P =.168). There was no significant difference in freedom from infection, rejection, or transplant coronary artery disease between the groups. By using Cox proportional hazard models, development of infection, rejection, and transplant coronary artery disease were independent predictors of decreased survival (P <.001, P =.004, and P =.004, respectively). CONCLUSIONS: These results demonstrate similar short-term and long-term survivals, as well as similar risks for infection and transplant coronary artery disease, in diabetic and nondiabetic patients undergoing cardiac transplantation. The trend toward worse survival in the diabetic cohort, however, raises the possibility that if a greater number of diabetic patients were evaluated, a significant difference in survival might be observed, suggesting the need for a multicenter analysis to validate these outcomes.

Prolonged donor ischemic time does not adversely affect long-term survival in adult patients undergoing cardiac transplantation.

OBJECTIVE: With liberalization of donor eligibility criteria, organs are being harvested from remote locations, increasing donor ischemic times. Although several studies have evaluated the effects of prolonged donor ischemic times on short-term survival and graft function, few have addressed concerns regarding long-term survival. METHODS: Over the last 11 years, 819 consecutive adults underwent cardiac transplantation at Columbia Presbyterian Medical Center. Recipients were separated into the following 4 groups based on donor ischemic time: <150 minutes, 150 to 200 minutes, 200 to 250 minutes, and >250 minutes. Statistical analysis included Kaplan-Meier survival and Cox proportional hazard models to identify predictors of long-term survival. RESULTS: Donor ischemic time was 120.1 +/- 21.1 minutes for group 1 (n = 321), 174.1 +/- 14.7 minutes for group 2 (n = 264), 221.7 +/- 14.6 minutes for group 3 (n = 154), and 295.5 +/- 37.1 minutes for group 4 (n = 80) (P <.001). There were no significant differences in recipient age, donor age, etiology of heart failure, United Network for Organ Sharing status, or history of previous cardiac surgery among the groups (P = NS). Prolonged donor ischemic time did not adversely affect long-term survival, with actuarial survival at 1, 5, and 10 years of 86.9%, 75.2%, and 56.4% for group 1; 86.2%, 76.9%, and 50.9% for group 2; 86.4%, 71.0%, and 43.7% for group 3; and 86.7%, 70.1%, and 50.9% for group 4 (P =.867). There was no significant difference in freedom from transplant coronary artery disease among the 4 groups (P =.474). CONCLUSIONS: Prolonged donor ischemic time is not a risk factor for decreased long-term survival. Procurement of hearts with prolonged donor ischemic time is justified in the setting of an increasing recipient pool with a fixed donor population.

Off-pump right atrial thrombectomy for heparin-induced thrombocytopenia with thrombosis.

This report describes a 72-year-old woman with atrial fibrillation who presented with lower extremity ischemia secondary to thromboembolism. After lower extremity thrombectomy, the patient developed heparin-induced thrombocytopenia with thrombosis (HITT). Her postoperative course was complicated by recurrent supraventricular and ventricular tachycardia, secondary to a mobile thrombus in the right atrium extending into the right ventricle. Because administration of heparin was contraindicated, the patient underwent off-pump right atrial thrombectomy during a brief period of inflow occlusion. Postoperatively, she was placed on lepirudin. Her platelet count normalized without any further thrombotic episodes, and she was discharged on warfarin.